Metal Availability and Transfer along Food Chains in Siena, a Small Medieval Town in Italy

Table 2

Mean Cd, Cu, Pb, and Zn concentrations (µg·g⁻¹ ± SD) in biotic and abiotic matrices from Siena vegetated walls (U) and extraurban control walls (C).

	Cd	Cu	Pb	Zn
Biological crusts (U)	0.66 ± 0.90	33.7 ± 19.8	64.8 ± 55.9	184 ± 123
Biological crusts (C)	0.25 ± 0.13	60.9 ± 48.0	22.4 ± 13.4	82 ± 38
Tortula muralis moss (U)	0.34 ± 0.13	64.6 ± 24.7	17.6 ± 6.1	106 ± 28
Tortula muralis moss (C)	0.21 ± 0.02	40.8 ± 24.5	9.2 ± 6.6	53.8 ± 6.74
Papillifera papillaris snail (tissues) (U)	1.70 ± 1.55	171 ± 53	1.09 ± 0.42	71.1 ± 51.2
Papillifera papillaris snail (tissues) (C)	0.69 ± 0.44	132 ± 72	0.50 ± 0.43	28.7 ± 5.2
Papillifera papillaris snail (feces) (U)	0.34 ± 0.14	157 ± 68	30.4 ± 12.8	62.3 ± 46
Papillifera papillaris snail (feces) (C)	0.45 ± 0.20	240 ± 117	31.1 ± 23.4	37.7 ± 23.2
Papillifera papillaris snail (shell) (U)	0.24 ± 0.09	46.6 ± 15.2	1.82 ± 0.46	261 ± 78
Papillifera papillaris snail (shell) (C)	0.14 ± 0.04	38.3 ± 9.8	1.70 ± 0.91	346 ± 111

Data source: [29].